I was reading a thread here a couple weeks ago and I thought it was a really good idea. A member made a DIY sponge filter using and enclosed loop with pvc that circled his tank with four sponges in the loop and two risers with his air pump creating the lift threw them for the water flow. Now what I am thinkin is to try in my new 75 setup I will try something similar but instead of the air pump I'll try a powerhead to power the sponge filter and hook the outtake to an UGJ system. Anybody have any experience with either of these.